U.S. patent number 6,409,682 [Application Number 08/881,586] was granted by the patent office on 2002-06-25 for intravascular guide wire and method for manufacture thereof.
This patent grant is currently assigned to SciMed Life Systems, Inc.. Invention is credited to Paul H. Burmeister, Richard E. Cappetta, Steven S. Hackett, Paul Slaikeu.
United States Patent |
6,409,682 |
Burmeister , et al. |
June 25, 2002 |
Intravascular guide wire and method for manufacture thereof
Abstract
A guide wire, and a method for the manufacture thereof, having a
core and a plastic jacket enclosing the core. The plastic jacket
comprises a proximal portion formed of a first plastic material and
a distal jacket portion formed of a second plastic material. The
distal end of the proximal jacket portion and the proximal end of
the distal jacket portion substantially abut each other and are of
substantially equal outer diameters so as to form a smooth
transition between the proximal and the distal jacket portions.
According to another aspect, there is provided a guide wire with a
selectively formable metallic core and a plastic jacket encasing
the formable core. The plastic jacket has a distal portion with a
hydrophilic coating and a proximal portion without a hydrophilic
coating. According to another aspect, there is provided a guide
wire having a formable metallic core and a plastic jacket encasing
the formable core. The plastic jacket has a distal portion that is
more radiopaque than a proximal portion.
Inventors: |
Burmeister; Paul H. (White Bear
Lake, MN), Cappetta; Richard E. (Plymouth, MN), Hackett;
Steven S. (Minnetonka, MN), Slaikeu; Paul (Vadnais
Heights, MN) |
Assignee: |
SciMed Life Systems, Inc.
(Maple Grove, MN)
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Family
ID: |
24878978 |
Appl.
No.: |
08/881,586 |
Filed: |
June 24, 1997 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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534113 |
Sep 26, 1995 |
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319772 |
Oct 7, 1994 |
5452726 |
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034174 |
Mar 12, 1993 |
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716678 |
Jun 18, 1991 |
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Current U.S.
Class: |
600/585; 600/434;
600/529 |
Current CPC
Class: |
A61M
25/09 (20130101); A61M 2025/09083 (20130101); A61M
2025/09091 (20130101); A61M 2025/09133 (20130101); A61M
2025/09175 (20130101); Y10T 29/49826 (20150115) |
Current International
Class: |
A61B
5/00 (20060101); A61B 005/00 () |
Field of
Search: |
;128/772,657
;604/95,164,280,281,282 ;600/585,529,434 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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0 340 304 |
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Nov 1989 |
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EP |
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0 380 102 |
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Aug 1990 |
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EP |
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0 395 098 |
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Oct 1990 |
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EP |
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0 405 823 |
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Jan 1991 |
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EP |
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0 407 965 |
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Jan 1991 |
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EP |
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2 401 668 |
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Aug 1977 |
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FR |
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60-12069 |
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Jan 1985 |
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JP |
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2-180277 |
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Jul 1990 |
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JP |
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WO 85/01444 |
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Apr 1985 |
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WO |
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WO 89/09626 |
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Oct 1989 |
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WO |
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WO 91/00051 |
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Jan 1991 |
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WO |
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Other References
Tegtmeyer, "Current Problems in Diagnostic Radiology", vol. XVI,
No. 2, Mar./Apr., 1987, pp. 79-80..
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Primary Examiner: Reip; David O.
Attorney, Agent or Firm: Crompton, Seager & Tufte,
LLC
Parent Case Text
This is a continuation of application Ser. No. 08/534,113, filed on
Sep. 26, 1995, now abandonded, which is a continuation of
application Ser. No. 08/319,772 filed on Oct. 7, 1994, now U.S.
Pat. No. 5,452,726, which is a continuation of U.S. Ser. No.
08/034,174, filed on Mar. 12, 1993, now abandoned , which is a
continuation of U.S. Ser. No. 07/716,678, filed on Jun. 18, 1991,
now abandoned.
Claims
We claim:
1. A guide wire comprising:
an elongated core having a length, a width, and an axial surface
defined thereby extending the length of said elongated core;
and
a plastic jacket extending around said axial surface of said
elongated core, said plastic jacket including a proximal jacket
portion and a distal jacket portion, said jacket portions formed of
a plastic material, wherein said distal jacket portion includes
means for enhancing the radiopaque properties of said distal jacket
portion relative to said proximal jacket portion incorporated
within said distal jacket portion.
2. The guide wire of claim 1, wherein said means for enhancing the
radiopaque properties of said distal jacket portion relative to
said proximal jacket portion include the incorporation of a
radiopaque material within said plastic of said distal jacket
portion.
3. The guide wire of claim 2, wherein the radiopaque material is a
compound containing bismuth.
4. The guide wire of claim 2, wherein said radiopaque material is
selected from a group consisting of barium or tungsten containing
compounds.
5. The guide wire of claim 1, wherein said core is made of
stainless steel.
6. The guide wire of claim 1, wherein the core is formable in a
distal portion thereof and non-formable in a proximal portion
thereof.
7. A guide wire comprising:
an elongated metallic core, said elongated metallic core having a
length and a width, said elongated metallic core further having an
axial surface extending the length of said elongated metallic core;
and
a plastic jacket encasing said elongated metallic core, said
plastic jacket having a distal portion and a proximal portion
formed of plastic materials, wherein the distal jacket portion
includes means for enhancing the radiopaque properties of said
distal jacket portion relative to said proximal jacket portion
incorporated within said distal jacket portion.
8. The guide wire of claim 7, wherein said means for enhancing the
radiopaque properties of said distal jacket portion relative to
said proximal jacket portion include the incorporation of a
radiopaque material within said plastic of said distal jacket
portion.
9. The guide wire of claim 8, wherein the radiopaque material is a
compound containing bismuth.
10. The guide wire of claim 8, wherein said radiopaque material is
selected from a group consisting of barium or tungsten containing
compounds.
11. The guide wire of claim 7, wherein said core is made of
stainless steel.
12. The guide wire of claim 7, wherein the core is formable in a
distal portion thereof and non-formable in a proximal portion
thereof.
Description
BACKGROUND OF THE INVENTION
The present invention relates to intravascular guide wires, and
methods of manufacture thereof. In particular, the present
invention relates to an intravascular guide wire, and methods for
the manufacture thereof, with improved properties to enhance the
use thereof.
Guide wires are used in various procedures in both the coronary
regions and the peripheral regions of the body. Various sizes and
lengths of guide wires are made to be suitable for various uses and
locations in the body. For example, guide wires of a very small
diameter, on the order of 0.010 to 0.018 inches may be suitable for
use in narrow coronary vessels. Such guide wires may have an
extremely floppy tip distal tip which may be bent or preformed by
the physician to facilitate placement of the guide wire at the
desired location. Other guide wires have larger diameter, for
example 0.035 inches. These larger diameter guide wires may be
especially useful in peripheral regions of the body. Larger
diameter guide wires may be provided with very flexible tips or
with relatively rigid tips depending upon the particular needs of
the patient and the preferences of the physician. Guide wires come
in a range of sizes in addition to those discussed above.
Some of the characteristics preferred in guide wires by some
physicians include strength, the ability to provide a track for a
balloon or other device to advance over, and good torsional
transmittance. A discussion of these and other preferred
characteristics of guide wires is in Endovascular Surgery, by
Moore, W. S. and Ahn, S. S; p. 157, W. B. Saunders Co. (1989). One
of the characteristics considered desirable by some physicians in a
guide wire is that it should be easy to grip and use manually at
the proximal portion.
Accordingly, it is an object of the present invention to provide a
guide wire with favorable characteristics.
SUMMARY OF THE INVENTION
According to a first aspect of the invention, there is provided a
guide wire, and a method for the manufacture thereof, having a core
and a plastic jacket enclosing the core. The plastic jacket
comprises a proximal portion formed of a first plastic material and
a distal jacket portion formed of a second plastic material. The
distal end of the proximal jacket portion and the proximal end of
the distal jacket portion are of substantially equal outer
diameters so as to form a smooth transition between the proximal
and the distal jacket portions.
According to another aspect of the invention, there is provided a
guide wire, and a method for the manufacture thereof, with a core
that is selectively formable in at least a distal portion thereof,
and a plastic jacket encasing the selectively formable core. The
plastic jacket has a distal portion with a hydrophilic coating and
a proximal portion without a hydrophilic coating.
According to another aspect of the invention, there is provided a
guide wire, and a method for the manufacture thereof, having a core
that is selectively formable, at least in a distal portion thereof,
and a plastic jacket encasing the core. The plastic jacket has a
distal portion that is more radiopaque than a proximal portion.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of a first embodiment of the present
invention.
FIG. 2a shows a cross section of the embodiment of FIG. 1 along
line 2a-2a'.
FIG. 2b shows a cross section of the embodiment of FIG. 1 along
line 2b-2b'.
FIG. 2c shows a cross section of the embodiment of FIG. 1 along
line 2c-2c'.
FIG. 3 is a sectional view of another embodiment of the present
invention.
FIG. 4 a sectional view of yet another embodiment of the present
invention.
DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS
Referring to FIG. 1 there is depicted a first preferred embodiment
of the present invention. This embodiment is an intravascular guide
wire 10. This guide wire 10 has a distal end 12 and a proximal end
14. The guide wire 10 may be approximately 180 centimeters in
length and have an outside diameter of approximately 0.035 inches.
Other lengths and diameters may be provided so that a range of
sizes of guide wires may be available suitable for the different
needs of various individual patients and the preferences of
physicians. Such other sizes are contemplated within the scope of
the present invention and of this embodiment in particular.
The guide wire 10 includes a core 18. The core may be made of a
strong, yet flexible material, such as a metal, like stainless
steel or nitinol, or other materials, or combinations thereof. In a
preferred embodiment, the core 18 is made at least in part of a
selectively formable metallic material, as explained in more detail
below. The core 18 extends from the distal end 12 to the proximal
end 14 of the guide wire 10.
In a preferred embodiment, the core 18 includes a distal portion 20
and a proximal portion 22. The proximal and distal portions are
preferably formed of a single metallic wire. The distal portion 20
has a smaller cross section than the proximal portion 22 to impart
greater flexibility to the distal end of the guide wire. In a
preferred embodiment, the distal portion 20 of the guide wire
comprises a series of stages or regions of tapered portions and
portions of uniform cross section, as explained in more detail
below. The series of stages of tapered portions and portions of
uniform cross section are intended to impart increasing levels of
flexibility to the guide wire toward the distal end.
In this embodiment, the proximal portion 22 of the core 18 has a
diameter of approximately 0.018 inches. FIG. 2a shows a cross
section of the guide wire in the proximal portion 22. The proximal
portion 22 of the core 18 extends from a proximal end of the guide
wire 10 to a proximal end of the distal portion 20 of the core 18.
In this embodiment, the distal portion 20 of the core 18 is
approximately 10.50 inches in length.
The distal portion 20 of the core includes a first region 24
immediately adjacent to and distal of the proximal portion 22. This
first region 24 of the distal portion 20 of the core is
approximately 2.0 inches in length. In the first region 24, the
core 18 tapers from the diameter of the proximal portion 20 (e.g.
0.018 inches) to a diameter of approximately 0.009 inches. In this
first region 24, the core has a circular cross section.
The distal portion 20 of the core next includes a second region 28
immediately adjacent to and distal of the first region 24. This
second region 28 of the distal portion 20 of the core is
approximately 4.0 inches in length. FIG. 2b shows a cross section
of the guide wire in this region. The second region 28 is a region
of approximately uniform cross section. In this second region 28,
the core also preferably has a circular cross section.
The distal portion 20 of the core next includes a third region 30
immediately adjacent to and distal of the second region 28. This
third region 30 of the distal portion 20 of the core is
approximately 2.0 inches in length. In the third region 30, the
core 18 tapers from the diameter of the second region 28 (e.g.
)0.0090 inches) to a diameter of approximately 0.00525 inches. In
this third region 30, the core also has a circular cross
section.
The distal portion 20 of the core next includes a fourth region 32
immediately adjacent to and distal of the third region 30. This
fourth region 32 of the distal portion 20 of the core is
approximately 1.75 inches in length. In the fourth region 32, the
core 18 is flattened toward a distal end 34 thereof to form a
ribbon shape having dimensions of approximately 0.010 by 0.00225
inches. FIG. 2c shows a cross section of the guide wire in this
region. The ribbon shape of this region causes the guide wire to
tend to flex in one plane thereby facilitating the use thereof. In
the fourth region 32, the length of the distal flattened portion is
approximately 0.5 inches, the length of the portion of circular
cross section is approximately 0.7 inches, and a transition zone
between these portions has a length of approximately 0.7
inches.
The distal portion 20 of the core wire, including the various
regions of tapered and uniform cross section, may be formed by
methods known in the art, such as chemical washes, polishes,
grinding, or compressing.
The guide wire 10 also includes a plastic jacket 38 extending from
the proximal end 14 to the distal end 12. In a first preferred
embodiment, the plastic jacket 38 is formed of a proximal jacket
portion 40 and a distal jacket portion 42. The outside diameter of
the plastic jacket 38 in this embodiment is approximately 0.035
inches although other diameters may be provided for guide wires of
other dimensions.
The distal jacket portion 42 is approximately 18 inches in length
and extends proximally from the distal end of the guide wire 10.
The distal end of the distal jacket portion 42 extends over and
covers the distal end of the core wire 18. The proximal jacket
portion 40 extends from the proximal end of the guide wire 10
distally. In this embodiment, the proximal end of the distal jacket
portion 42 substantially abuts the distal end of the proximal
jacket portion 40. At the location at which the proximal and distal
jacket portions abut, the outside diameters of the jacket portions
are substantially the same and form a smooth transition at that
location so that the guide wire can be readily inserted into and
moved within a catheter or vessel or that a catheter or other
device can be readily advanced over the guide wire.
These two jacket portions are provided to yield features related to
functions specifically associated with their respective locations.
In this embodiment, the proximal jacket portion 40 is made of a
Teflon.RTM., i.e., polytetraflouroethylene, material and the distal
jacket portion 42 is made of polyurethane. Alternatively, the
proximal jacket portion 40 may be made of another material or
combination of materials, such as flouroresins, such as Kynar
(CH.sub.2 CF.sub.2), high density polyethylene, Delrin
(polyacetal), Hytrel or polypropylene. The distal jacket portion 42
may be made of other polymers or copolymers, or elastomers, or
fluoroelastomers or silicone, Hytrel or nylon.
In a preferred embodiment, the distal jacket portion has a
hydrophilic coating applied to it to make the surface highly
lubricious when it comes in contact with a fluid such as blood. The
hydrophilic coating is believed to improve the biocompatability of
the guide wire. This is based in part on observations that
hydrophilic surfaces are generally less thrombogenic, and more
specifically, tend to exhibit reduced platelet activation and
aggregation compared to hydrophobic surfaces. In a preferred
embodiment, the composition of the coating is a mixture of a
hydrogel and a polyurethane in an organic/ water solvent mixture.
The solution mixture is applied to the distal jacket portion 42 and
dried. In a preferred embodiment, polyvinyl pyrrolidone (PVP) is
used as the hydrogel and commercial polyurethanes such as Dow
(Pellethane 2363 Series) or Thermedics (the Tecophane or Tecoflex
families) may be used. A polymer blend having an affinity to the
polyurethane substrate of the distal jacket portion (via the
urethane and the solution) is used while the other component is a
slippery otherwise water-soluble material. The hydrogel will not
tend to dissolve away because it is ensnared with the water
insoluble polyurethane.
As an alternative to using a hydrophilic coating, a different
coating may be applied to the guide wire jacket to enhance its
lubriciousness. Such a coating may be a silicone coating or other
lubricious material.
In a preferred embodiment, the hydrophilic coating is applied only
to a distal portion of the guide wire, and in particular, only to
the distal jacket portion 42. This is facilitated because the
preferred hydrophilic coating is formulated to adhere to the
urethane material of the distal jacket portion but not adhere to
many different materials including the preferred material of the
proximal jacket.
As mentioned above, the proximal jacket portion is made of Teflon,
i.e., polytetraflouroethylene, which also provides a low friction
surface though not as low friction as that of the distal jacket
portion with the hydrophilic coating applied. It is advantageous
for the proximal portion of the guide wire have a low friction
surface in order to traverse a catheter lumen or a vessel. However,
because the proximal portion of the guide wire will likely be in a
portion of the vasculature not as tortuous as the distal portion,
it would not require a surface of as high lubricity as the distal
portion and therefore Teflon, i.e., polytetraflouroethylene, is a
good choice of materials.
Moreover, this combination of low friction surfaces has the
additional advantage that a very low friction surface, such as one
having a hydrophilic coating, is used only on the distal portion of
the guide wire. A very low friction surface, such as one having a
hydrophilic coating, would be so slippery that it would be
difficult for a physician to handle if it were on the proximal end
as well. Accordingly, at the proximal end of the guide wire, this
embodiment includes a surface that is easy for the physician who
would be manipulating the guide wire from the proximal end to
handle and yet is of sufficiently low friction so that it can
readily traverse portions of the patient's vessels and provide good
guide wire movement in a catheter.
It is also preferred that the distal portion of the guide wire be
provided with enhanced radiopaque properties. In the preferred
embodiment, this is done by loading the material from which the
distal jacket 42 is made with radiopaque materials such as barium,
bismuth or tungsten. The loading of the distal jacket of
polyurethane with a radiopaque material enhances the ability of a
physician to observe the position of the distal end of the guide
wire in the body of the patient by means of fluoroscopy.
In a preferred embodiment, the proximal jacket portion 40 of Teflon
i.e., polytetraflouroethylene. is heat shrunk onto the core wire.
The distal jacket portion 42 is installed over the core wire by
heating a sleeve of polyurethane to a temperature until it is
reformed around the core wire. The proximal and distal jackets may
be finished by a centerless grinding method so that the transition
between the jacket portions is smooth.
In a further embodiment, the guide wire has a core that is
selectively formable at least in a distal portion thereof. By a
selectively formable core, it is meant that the wire from which the
core is made may be bent to a particular shape and that the shape
will be maintained by the wire. This allows the physician to impart
a particular shape to the guide wire, by bending or kinking it for
example, to facilitate its placement into a patient's vasculature.
To provide this selective formability, in a preferred embodiment,
the entire core wire may be made of stainless steel. Other
materials may be used to provide this feature. The use of a
formable material, such as stainless steel, provides advantages in
the guide wire over materials that cannot be formed, such as
superelastic materials like nitinol. Superelastic materials, like
nitinol, are so resilient that they tend to spring back to their
original shape even if bent, thus are not formable. Although
superelastic material may be provided with a "preformed" memory
shape, such a preformed shape is typically determined in the
manufacture of the guide wire and cannot readily be altered or
modified by the physician by simply bending the guide wire prior to
use. Although use of superelastic materials such as nitinol in
guide wire applications may provide some advantages in certain
uses, a formable core, such as of stainless steel, which can be
formed by the physician to a shape suitable for a particular
patient or preferred by that physician, provides an advantage that
cannot be obtained with a superelastic core guide wire.
In a further preferred embodiment, the guide wire may include a
core wire of a material having formable properties at a distal
portion thereof and non-formable (e.g. superelastic properties)
proximally. Such a construction would provide advantages in certain
guide wire usages. A guide wire having these properties could be
formed by using a superelastic material such as nitinol for the
core wire and reducing its superelasticity in a distal portion
thereof. This may be effected by heating the distal end of the
superelastic core wire. Another means to reduce the superelastic
properties of a distal end of the core wire would be to shape it
mechanically, e.g. flattening it. Other methods of reducing the
superelastic properties of the core wire may also be used. With a
core wire having this dual combination of a formable distal portion
and a superelastic proximal portion, desired shapes could be
imparted by a physician to the distal end of the guide wire to
facilitate making turns, etc., in tortuous vessel passages, while
in the same guide wire the more proximal portion would possess
superelastic properties to allow it to follow the distal portion
through the tortuous passages without permanently deforming. This
combination of formable and non-formable properties in the core
wire may also be provided by using more than one material for the
core wire or more than one wire.
FIG. 3 shows another preferred embodiment of the present invention.
This embodiment of the guide wire is similar in some respects to
the embodiment of the guide wire, described above. Although this
embodiment of the guide wire may be provided in large sizes (e.g.
0.035 inches), this embodiment is especially suitable for a guide
wire of a smaller diameter, e.g. having an outer diameter of
approximately 0.018 inches. If provided in a guide wire of smaller
diameter, the diameter of the core wire and plastic jacket would be
correspondingly smaller. Like the embodiment described above, this
guide wire includes a core 52 surrounded by a plastic jacket 54.
The core 52 is preferably of a selectively formable material, as
described above. In addition, in this embodiment, a marker 56 is
provided at a distal end 58 of the guide wire 50. This marker 56 is
located around the distal portion of the core wire 52 underneath
the plastic jacket 54. In this embodiment, the marker 56 is a coil
spring. Alternatively, the marker may be a ribbon, another wire, or
any other similar component. A tip 60 may be provided at the distal
end of the core wire 52 to facilitate placement and connection of
the marker 56.
The marker 56 may be made of platinum or stainless steel or other
material. The marker 56 may be provided with radiopaque properties
by selecting a material such as platinum. This may be in addition
or as an alternative to providing radiopaque properties in the
jacket portion through the use of loading with radiopaque
materials. The use of a radiopaque marker may be preferred in
smaller diameter guide wires where the plastic jacket, even if
loaded with a radiopaque material, is of such a small size that it
could be difficult to discern under fluoroscopy.
FIG. 4 shows another preferred embodiment of the present invention.
In the embodiment in FIG. 4, a core wire 20 extends from a distal
to a proximal end of the guide wire. As in the embodiment described
above, the core wire 20 is surrounded by a core wire jacket 38. In
this embodiment, the core wire jacket 38 is comprised of a first
jacket 70. The first jacket 70 of this embodiment is comprised of a
first portion 72 and a second portion 74. The core wire jacket 38
also includes a second jacket 76. The second jacket 76 covers the
first jacket 70 over the second portion 74 thereof. The second
jacket 76 may correspond to the proximal jacket of the previous
embodiments. The second jacket 76 may be a thin tubing that is heat
shrunk onto the first jacket 70 over a proximal portion thereof.
Alternatively, the second jacket 76 may be applied by other
methods, such as by spraying, dipping, etc.
In a preferred embodiment, the outer diameter of the second jacket
76 when it is in position surrounding the first jacket 70 is
approximately the same as the outer diameter of the first jacket 70
in the first portion 72 thereof at least in an area 80 of the guide
wire where the second jacket 76 ends so that the overall diameter
of the guide wire through this area 80 is substantially uniform.
This uniformity may be further enhanced by polishing, grinding, or
other means. To further provide for this uniformity in diameter,
the second portion 74 of the first jacket 70 may be provided with a
diameter that is less than that of the first portion 72 of the
first jacket 70. This reduction in diameter may be formed by
grinding, stretching, chemical erosion, or other means.
In a preferred embodiment, the second jacket 76 covers the proximal
portion of the guide wire and an exposed first portion 72 of the
first jacket 70 extends to a distal end of the guide wire. The
first jacket 70 and second jacket 76 may be provided with
properties specifically directed to their respective functions, as
explained above in regard to the embodiment of the guide wire in
which the jackets are in an abutting relationship. For example, the
first jacket 70 may be made of polyurethane and the second jacket
76 may be made of a Teflon-like, i.e., polytetraflouroethylene,
material. A hydrophilic coating may be applied to the first jacket
70 in the first portion 72 thereof to enhance lubricity, as
explained above. If this embodiment of the guide wire is intended
for use in peripheral regions of the body, it may have an outside
diameter of approximately 0.035 inches. Other dimensions may be
suitable as well for other size guide wires. As in the previously
described embodiments, the core 20 may be a material such as
stainless steel or nitinol and may have formable properties in at
least a portion thereof.
It is intended that the foregoing detailed description be regarded
as illustrated rather than limiting and that it is understood that
the following claims including all equivalents are intended to
define the scope of the invention.
* * * * *